During hospitalisation or a surgical procedure, there may be a need to swap a single lumen catheter to a multi-lumen or vice versa. An anesthetist may need to swap a single lumen catheter for a multi-lumen catheter, for example, to provide an additional channel for drug administration or pressure measurement. Using present techniques, the existing catheter is typically removed over a guidewire, and the replacement catheter is fed over the same guidewire to the location of the previous catheter. The procedure entails some risk. Notably, it is traumatic and can give rise to complications such as pneumothorax, hematothorax, nerve damage, accidental puncture of arteries, and stroke. Moreover, the handling of a second catheter leads to an increased risk of infection.
Classical multichannel catheters are made from an extruded solid tube containing multiple channels. A classical two channel (dual lumen) catheter 242 of the art is shown in FIG. 1, inserted through the jugular vein 112 into the right atrium 114 of the heart of a subject 110. Owing to the extrusion process, the internal channel walls are relatively thick, and the catheter is stiffer compared with a single lumen device. Any catheter is preferably soft in order to be minimally traumatic in respect of endothelium damage due to insertion and cardiac pulsations; existing multichannel catheter will less fulfill this preference due to the thickness of internal walls.
Normal pressure hydrocephalus (NPH) is characterized by a triad of cognitive impairment, gait disturbance and nocturesis. The diagnosis is often difficult due to the symptoms being similar to other disorders such as dementia or Parkinson's disease. Many patients go completely unrecognized and are never treated. The condition is due to the fact the intracranial pressure (ICP) pressure is abnormal. It has been confirmed that pressure is increased due reduced absorption capacity. Therefore, a shunting device which drains the cerebro-spinal fluid (CSF) from the brain towards the abdomen or bloodstream is the principal therapy.
Several diagnostic procedures are currently used to make the diagnosis of NPH, which include magnetic resonance imaging (MRI), a lumbar puncture tap test, or measurement of absorption capacity. For the latter, saline is infused into the CSF space while the pressure is measured. A steep rise in pressure indicates reduced absorption. Infusion is normally performed through a lumbar puncture needle while the pressure is monitored through a second lumbar puncture needle. Some neurosurgeons use one large diameter needle for both infusion and monitoring. Infusion and monitoring through one fine needle is impossible since the dynamic resistance causes a false increased pressure reading. The issue with multiple or large lumbar puncture needles is the discomfort for the patient and the higher risk of post puncture hypotension headache. In the case of a large diameter needle, the small hole in the lumbar spinal dura caused by the puncture does not close spontaneously after measurement. In upright position the high hydrostatic pressure will cause an escape of CSF. The reduced pressure in the brain causes severe headaches.
There is thus a need for a device which can overcome the problems of the art.